Combined Parchment

 is an item in Tyranny.

Description
Combined with the first two parchment pieces you found, you can see a crudely drawn Rho sigil in the center, a crudely drawn Citren sigil in the upper lefthand corner, and a crudely drawn Amith sigil in the upper righthand corner.

Location

 * Twin Rivers Oldwalls - Depths: Find the other two parchments. The third one is on the Bronze Brotherhood corpse in the room near the plateau with the Rho Torchkey.